U.S. patent application number 13/197194 was filed with the patent office on 2012-06-28 for photosensitive resin composition and color filter using the same.
This patent application is currently assigned to CHEIL INDUSTRIES INC.. Invention is credited to Gyu-Seok Han, Han-Chul Hwang, Ju-Ho Jung, Dong-Wan Kim, Jae-Hyun Kim, Ji-Yun Kwon, In-Jae Lee, Dong-Won Song.
Application Number | 20120161087 13/197194 |
Document ID | / |
Family ID | 46315523 |
Filed Date | 2012-06-28 |
United States Patent
Application |
20120161087 |
Kind Code |
A1 |
Jung; Ju-Ho ; et
al. |
June 28, 2012 |
Photosensitive Resin Composition and Color Filter Using the
Same
Abstract
A photosensitive resin composition for a color filter including
a colorant including a dye represented by the following Chemical
Formula 1, (B) an acrylic-based binder resin, (C) a
photopolymerizable monomer, (D) a photopolymerization initiator,
and (E) a solvent, and a color filter using the same are provided.
##STR00001## In Chemical Formula 1, each substituent is the same as
defined in the detailed description.
Inventors: |
Jung; Ju-Ho; (Uiwang-si,
KR) ; Kwon; Ji-Yun; (Uiwang-si, KR) ; Lee;
In-Jae; (Uiwang-si, KR) ; Kim; Dong-Wan;
(Uiwang-si, KR) ; Kim; Jae-Hyun; (Uiwang-si,
KR) ; Song; Dong-Won; (Uiwang-si, KR) ; Han;
Gyu-Seok; (Uiwang-si, KR) ; Hwang; Han-Chul;
(Uiwang-si, KR) |
Assignee: |
CHEIL INDUSTRIES INC.
Gumi-si
KR
|
Family ID: |
46315523 |
Appl. No.: |
13/197194 |
Filed: |
August 3, 2011 |
Current U.S.
Class: |
252/586 ;
430/286.1 |
Current CPC
Class: |
G03F 7/0007 20130101;
G02B 5/223 20130101; G03F 7/031 20130101; C09B 45/06 20130101; G03F
7/105 20130101; C09B 45/34 20130101; G03F 7/027 20130101 |
Class at
Publication: |
252/586 ;
430/286.1 |
International
Class: |
G03F 7/028 20060101
G03F007/028; G02B 5/23 20060101 G02B005/23; G03F 7/038 20060101
G03F007/038 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 27, 2010 |
KR |
10-2010-0135699 |
Claims
1. A photosensitive resin composition for a color filter comprising
(A) a colorant including a dye represented by the following
Chemical Formula 1; (B) an acrylic-based binder resin; (C) a
photopolymerizable monomer; (D) a photopolymerization initiator;
and (E) a solvent: ##STR00007## wherein, in Chemical Formula 1,
R.sup.11 to R.sup.14 are the same or different and are
independently a single bond or oxygen, R.sup.15 to R.sup.20 are the
same or different and are independently hydrogen, hydroxyl,
substituted or unsubstituted amine, nitro, substituted or
unsubstituted C1 to C20 alkoxy, substituted or unsubstituted C1 to
C20 alkyl, substituted or unsubstituted C2 to C20 alkenyl,
substituted or unsubstituted C2 to C20 alkynyl, substituted or
unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C3
to C20 cycloalkenyl, substituted or unsubstituted C3 to C20
cycloalkynyl, substituted or unsubstituted C2 to C20
heterocycloalkyl, substituted or unsubstituted C2 to C20
heterocycloalkenyl, substituted or unsubstituted C2 to C20
heterocycloalkynyl, substituted or unsubstituted C6 to C30 aryl, or
substituted or unsubstituted C6 to C30 aryloxy, n.sup.11 to
n.sup.16 are the same or different and are independently integers
ranging from 0 to 4, and Y is Na, K, Ca, Mg, Al, Zn, or Fe.
2. The photosensitive resin composition for a color filter of claim
1, wherein the dye comprises a compound represented by the
following Chemical Formula 2: ##STR00008##
3. The photosensitive resin composition for a color filter of claim
1, wherein the dye has a solubility for a solvent of about 3 to
about 20.
4. The photosensitive resin composition for a color filter of claim
1, wherein the dye has a maximum absorption wavelength at about 400
to about 460 nm wavelength region.
5. The photosensitive resin composition for a color filter of claim
1, wherein the dye has a transmittance of about 85 to about 100% at
about 500 to about 800 nm wavelength region.
6. The photosensitive resin composition for a color filter of claim
1, wherein the dye has a thermal decomposition temperature of about
150 to about 400.degree. C.
7. The photosensitive resin composition for a color filter of claim
1, wherein the colorant further comprises a pigment.
8. The photosensitive resin composition for a color filter of claim
7, wherein the colorant comprises the dye and the pigment at a
weight ratio of about 1:9 to about 9:1.
9. The photosensitive resin composition for a color filter of claim
1, wherein the photosensitive resin composition for a color filter
comprises about 1 to about 30 wt % of the colorant; about 1 to
about 30 wt % of the acrylic-based binder resin; about 1 to about
15 wt % of the photopolymerizable monomer; about 0.1 to about 10 wt
% of the photopolymerization initiator; and balance of the
solvent.
10. The photosensitive resin composition for a color filter of
claim 1, wherein the acrylic-based binder resin comprises a
copolymer of a first ethylenic unsaturated monomer comprising
(meth)acrylic acid, maleic acid, itaconic acid, fumaric acid, or a
combination thereof; and a second ethylenic unsaturated monomer
comprising styrene, .alpha.-methylstyrene, vinyltoluene,
vinylbenzylmethylether, methyl(meth)acrylate, ethyl(meth)acrylate,
butyl(meth)acrylate, 2-hydroxyethyl(meth)acrylate, 2-hydroxy
butyl(meth)acrylate, benzyl(meth)acrylate,
cyclohexyl(meth)acrylate, phenyl(meth)acrylate,
2-aminoethyl(meth)acrylate, 2-dimethylaminoethyl(meth)acrylate,
vinyl actate, vinyl benzoate, glycidyl(meth)acrylate,
(meth)acrylonitrile, (meth)acrylamide, or a combination
thereof.
11. The photosensitive resin composition for a color filter of
claim 1, wherein the photopolymerizable monomer comprises ethylene
glycol di(meth)acrylate, diethylene glycol di(meth)acrylate,
triethylene glycol di(meth)acrylate, propylene glycol
di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,4-butanediol
di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, bisphenol A
di(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol
tri(meth)acrylate, pentaerythritol tetra(meth)acrylate,
pentaerythritol hexa(meth)acrylate, dipentaerythritol
di(meth)acrylate, dipentaerythritol tri(meth)acrylate,
dipentaerythritol penta(meth)acrylate, dipentaerythritol
hexa(meth)acrylate, bisphenol A epoxy(meth)acrylate, ethylene
glycol monomethylether (meth)acrylate, trimethylol propane
tri(meth)acrylate, tris(meth)acryloyloxyethyl phosphate, novolac
epoxy (meth)acrylate, or a combination thereof.
12. The photosensitive resin composition for a color filter of
claim 1, further comprising malonic acid; 3-amino-1,2-propanediol;
a silane-based coupling agent including a vinyl group or a
(meth)acryloxy group; a leveling agent; a fluorine-based
surfactant; a radical polymerization initiator; or a combination
thereof.
13. A color filter manufactured using the photosensitive resin
composition of claim 1.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority under 35 USC Section 119 to
and the benefit of Korean Patent Application No. 10-2010-0135699
filed in the Korean Intellectual Property Office on Dec. 27, 2010,
the entire disclosure of which is incorporated herein by
reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a photosensitive resin
composition and a color filter using the same.
BACKGROUND
[0003] Color filters are used in liquid crystal displays (LCDs),
optical filters for cameras, and the like. Color filters may be
fabricated by coating a fine region with three or more colors on a
charge-coupled device or a transparent substrate. The colored thin
film can be fabricated by dyeing, printing, electrophoretic
deposition (EPD), pigment dispersion, and the like.
[0004] The pigment dispersion method forms a colored film by
repeating a series of processes such as coating, exposing to a
light, developing, and curing a photopolymer composition including
a coloring agent on a transparent substrate including a black
matrix. The pigment dispersion method can improve heat resistance
and durability, which are very important characteristics for a
color filter, and can provide a film with a uniform thickness.
[0005] However, in the pigment dispersion method, the pigment may
be not dissolved in a solvent and thus may remain as a dispersion.
Accordingly, the pigment dispersion method can be limited with
regard to improving the color characteristics of contrast ratio
since the pigment particles may reflect, diffract, refract, or
interfer with light when light is transmitted.
SUMMARY
[0006] One embodiment of the present invention provides a
photosensitive resin composition for a color filter that can have a
high contrast ratio, high luminance, and excellent durability.
[0007] Another embodiment of the present invention provides a color
filter using the photosensitive resin composition for a color
filter.
[0008] According to one embodiment of the present invention, a
photosensitive resin composition for a color filter of the present
invention includes (A) a colorant including a dye represented by
the following Chemical Formula 1; (B) an acrylic-based binder
resin; (C) a photopolymerizable monomer; (D) a photopolymerization
initiator; and (E) a solvent.
##STR00002##
[0009] In Chemical Formula 1,
[0010] R.sup.11 to R.sup.14 are the same or different and are
independently a single bond or oxygen,
[0011] R.sup.15 to R.sup.20 are the same or different and are
independently hydrogen, hydroxyl, substituted or unsubstituted
amine, nitro, substituted or unsubstituted C1 to C20 alkoxy,
substituted or unsubstituted C1 to C20 alkyl, substituted or
unsubstituted C2 to C20 alkenyl, substituted or unsubstituted C2 to
C20 alkynyl, substituted or unsubstituted C3 to C20 cycloalkyl,
substituted or unsubstituted C3 to C20 cycloalkenyl, substituted or
unsubstituted C3 to C20 cycloalkynyl group, substituted or
unsubstituted C2 to C20 heterocycloalkyl, substituted or
unsubstituted C2 to C20 heterocycloalkenyl, substituted or
unsubstituted C2 to C20 heterocycloalkynyl, substituted or
unsubstituted C6 to C30 aryl, or substituted or unsubstituted C6 to
C30 aryloxy,
[0012] n.sup.11 to n.sup.16 are the same or different and are
independently integers ranging from 0 to 4, and
[0013] Y is Na, K, Ca, Mg, Al, Zn, or Fe.
[0014] The dye of the above Chemical Formula 1 may include a
compound represented by the following Chemical Formula 2.
##STR00003##
[0015] The dye may have a solubility in a solvent of about 3 to
about 20, a maximum absorption wavelength at about 400 to about 460
nm wavelength region, transmittance of about 85 to about 100% at
about 500 to about 800 nm wavelength region, and a thermal
decomposition temperature of about 150 to about 400.degree. C.
[0016] The colorant may further include a pigment.
[0017] The colorant may include the dye and the pigment at a weight
ratio of about 1:9 to about 9:1:
[0018] The photosensitive resin composition for a color filter may
include about 1 to about 30 wt % of the colorant; about 1 to about
30 wt % of the acrylic-based binder resin; about 1 to about 15 wt %
of the photopolymerizable monomer; about 0.1 to about 10 wt % of
the photopolymerization initiator; and balance of the solvent.
[0019] The acrylic-based binder resin may include a copolymer of a
first ethylenic unsaturated monomer such as but not limited to
(meth)acrylic acid, maleic acid, itaconic acid, fumaric acid, or a
combination thereof; and a second ethylenic unsaturated monomer
such as but not limited to styrene, .alpha.-methylstyrene,
vinyltoluene, vinylbenzylmethylether, methyl(meth)acrylate,
ethyl(meth)acrylate, butyl(meth)acrylate,
2-hydroxyethyl(meth)acrylate, 2-hydroxy butyl(meth)acrylate,
benzyl(meth)acrylate, cyclohexyl(meth)acrylate,
phenyl(meth)acrylate, 2-aminoethyl(meth)acrylate,
2-dimethylaminoethyl(meth)acrylate, vinyl actate, vinyl benzoate,
glycidyl(meth)acrylate, (meth)acrylonitrile, (meth)acrylamide, or a
combination thereof.
[0020] The photopolymerizable monomer may include without
limitation ethylene glycol di(meth)acrylate, diethylene glycol
di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene
glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate,
1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate,
bisphenol A di(meth)acrylate, pentaerythritol di(meth)acrylate,
pentaerythritol tri(meth)acrylate, pentaerythritol
tetra(meth)acrylate, pentaerythritol hexa(meth)acrylate,
dipentaerythritol di(meth)acrylate, dipentaerythritol
tri(meth)acrylate, dipentaerythritol penta(meth)acrylate,
dipentaerythritol hexa(meth)acrylate, bisphenol A
epoxy(meth)acrylate, ethylene glycol monomethylether
(meth)acrylate, trimethylol propane tri(meth)acrylate,
tris(meth)acryloyloxyethyl phosphate, novolac epoxy (meth)acrylate,
or a combination thereof.
[0021] The photosensitive resin composition for a color filter may
further include one or more additives such as but not limited to
malonic acid; 3-amino-1,2-propanediol; a silane-based coupling
agent including a vinyl group or a (meth)acryloxy group; a leveling
agent; a fluorine-based surfactant; a radical polymerization
initiator; or a combination thereof.
[0022] According to another embodiment of the present invention a
color filter manufactured using the photosensitive resin
composition is provided.
[0023] Hereinafter, other embodiments will be described in
detail.
[0024] The photosensitive resin composition for a color filter can
have a high contrast ratio and high luminance, and excellent
durability, and therefore can be used in the production of a color
filter.
DETAILED DESCRIPTION
[0025] The present invention will be described more fully
hereinafter in the following detailed description of the invention,
in which some but not all embodiments of the invention are
described. Indeed, this invention may be embodied in many different
forms and should not be construed as limited to the embodiments set
forth herein; rather, these embodiments are provided so that this
disclosure will satisfy applicable legal requirements.
[0026] As used herein, when a specific definition is not otherwise
provided, the term "substituted" refers to one substituted with a
substituent including halogen (F, Cl, Br or I), hydroxyl, C1 to C20
alkoxy, nitro, cyano, amine, imino, azido, amidino, hydrazino,
hydrazono, carbonyl, carbamyl, thiol, ester, ether, carboxyl or a
salt thereof, sulfonic acid or a salt thereof, phosphoric acid or a
salt thereof, C1 to C20 alkyl, C2 to C20 alkenyl, C2 to C20
alkynyl, C6 to C30 aryl, C3 to C20 cycloalkyl, C3 to C20
cycloalkenyl, C3 to C20 cycloalkynyl, C2 to C20 heterocycloalkyl,
C2 to C20 heterocycloalkenyl, C2 to C20 heterocycloalkynyl, C3 to
C30 heteroaryl, or a combination thereof, in place of at least one
hydrogen.
[0027] As used herein, when a specific definition is not otherwise
provided, the term "hetero" may refer to a cyclic group in which
one or more hydrogen atoms are substituted with one or more
heteroatoms comprising N, O, S, P, or a combination thereof.
[0028] As used herein, when a specific definition is not otherwise
provided, the term "(meth)acrylate" refers to both "acrylate" and
"methacrylate", and the term "(meth)acrylic acid" refers to
"acrylic acid" and "methacrylic acid".
[0029] The photosensitive resin composition for a color filter
according to one embodiment includes (A) a colorant, (B) an
acrylic-based binder resin, (C) a photopolymerizable monomer, (D) a
photopolymerization initiator, and (E) a solvent.
[0030] Hereinafter, each component is described in detail.
[0031] (A) Colorant
[0032] The colorant may include a dye such as an imidazole chromium
complex, and the dye may be represented by the following Chemical
Formula 1.
##STR00004##
[0033] In Chemical Formula 1:
[0034] R.sup.11 to R.sup.14 are the same or different and are
independently a single bond or oxygen,
[0035] R.sup.15 to R.sup.20 are the same or different and are
independently hydrogen, hydroxyl, substituted or unsubstituted
amine, nitro, substituted or unsubstituted C1 to C20 alkoxy,
substituted or unsubstituted C1 to C20 alkyl, substituted or
unsubstituted C2 to C20 alkenyl, substituted or unsubstituted C2 to
C20 alkynyl, substituted or unsubstituted C3 to C20 cycloalkyl,
substituted or unsubstituted C3 to C20 cycloalkenyl, substituted or
unsubstituted C3 to C20 cycloalkynyl, substituted or unsubstituted
C2 to C20 heterocycloalkyl, substituted or unsubstituted C2 to C20
heterocycloalkenyl, substituted or unsubstituted C2 to C20
heterocycloalkynyl, substituted or unsubstituted C6 to C30 aryl,
substituted or unsubstituted C6 to C30 aryloxy, or a combination
thereof,
[0036] n.sup.11 to n.sup.16 are the same or different and are
independently integers ranging from 0 to 4, and
[0037] Y is Na, K, Ca, Mg, Al, Zn, or Fe.
[0038] An example of the dye includes but is not limited to a
compound represented by the following Chemical Formula 2.
##STR00005##
[0039] The dye may be a red dye.
[0040] The dyes of Chemical Formula 1 may be commerically available
and/or may be produced using commercially available starting
materials by the skilled artisan without undue experimentation.
[0041] Unlike a pigment having particles, the dye of Chemical
Formula 1 can have good solubility in a solvent, and thus when
dissolved in a solvent the dye has no particles or very small
particles having a first particle diameter of about 1 to about 10
nm. Further, the dye of Chemical Formula 1 can have high
durability. When the dye has a significantly smaller diameter than
the pigment, there may be less optical scattering, which can
improve contrast ratio. Thereby, the dye of Chemical Formula 1 may
compensate for the deterioration of contrast ratio and luminance
which has been a problem when using conventional pigment dispersion
methods to fabricate a color filter.
[0042] The dye may have a solubility in a solvent of about 3 to
about 20, for example about 3 to about 12. As used herein, and as
will be appreciated and understood by the skilled artisan, the
solubility of the dye refers to an amount (g) of the dye dissolved
in about 100 g of a solvent, such as any of the solvents listed
herein, at room temperature. As also will be appreciated and
understood by the skilled artisan, solubility as used herein is not
expressed in terms of a specific unit.
[0043] When the dye has a solubility within the above range, the
dye may not decompose and further may provide excellent coloring
properties and compatibility with other components of the
photosensitive resin composition for a color filter.
[0044] The dye may have a maximum absorption wavelength at about
400 to about 460 nm wavelength region during spectroscopic
analysis. The dye may also have a transmittance of about 85 to
about 100% at about 500 to about 800 nm wavelength region during
spectroscopic analysis. When the dye has a maximum absorption
wavelength and a transmittance within the above ranges, it may have
high luminance.
[0045] The dye can have a high heat resistance. In other words, the
thermal decomposition temperature of the dye may range from about
150 to about 400.degree. C. as measured by a thermogravimetric
analyzer (TGA).
[0046] The dye having these characteristics can have a high
luminance and a high contrast ratio in the desirable color
coordinate, and it may be used in the production of a LCD color
filter including a backlight of a CCFL or a LED.
[0047] The photosensitive resin composition for a color filter may
further include another dye, such as a yellow dye, in addition to
or instead of the red dye.
[0048] According to one embodiment, the colorant may include only
the dye or may include a dye mixed with a pigment for improving
durability.
[0049] The pigment may include a red pigment, a yellow pigment, or
a combination thereof.
[0050] The red pigment may include a compound having at least one
azo group. Examples of the red pigment may include without
limitation C.I. pigment red 254, C.I. pigment red 242, C.I. pigment
red 214, C.I. pigment red 221, C.I. pigment red 166, C.I. pigment
red 220, C.I. pigment red 248, C.I. pigment red 262, and the like,
and combinations thereof.
[0051] Examples of the yellow pigment may include without
limitation C.I. pigment yellow 139, C.I. pigment yellow 138, C.I.
pigment yellow 150, and the like, and combinations thereof.
[0052] For example, the colorant may be prepared by mixing the dye
and the pigment at a weight ratio of about 1:9 to about 9:1 or at a
weight ratio of about 3:7 to about 7:3. In some embodiments, the
mixture of the dye and the pigment may include the dye in an amount
of about 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,
58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,
75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, or 90
wt %. Further, according to some embodiments of the present
invention, the amount of dye in the mixture of the dye and the
pigment can be in a range from about any of the foregoing amounts
to about any other of the foregoing amounts.
[0053] In some embodiments, the mixture of the dye and the pigment
may include the pigment in an amount of about 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,
66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82,
83, 84, 85, 86, 87, 88, 89, or 90 wt %. Further, according to some
embodiments of the present invention, the amount of the pigment in
the mixture of the dye and the pigment can be in a range from about
any of the foregoing amounts to about any other of the foregoing
amounts.
[0054] When the dye and the pigment are mixed at the above weight
ratio range, they may provide a high contrast ratio while
maintaining the color characteristics.
[0055] The photosensitive resin composition may include the
colorant in an amount of about 1 to about 30 wt %, for example,
about 3 to about 25 wt %, based on the total weight of the
photosensitive resin composition for a color filter. In some
embodiments, the photosensitive resin composition may include the
colorant in an amount of about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28,
29, or 30 wt %. Further, according to some embodiments of the
present invention, the amount of the colorant can be in a range
from about any of the foregoing amounts to about any other of the
foregoing amounts. When the colorant is included in an amount
within the above range, it may provide excellent color
characteristics and high contrast ratio in the same color
coordinate.
[0056] (B) Acrylic-Based Binder Resin
[0057] The acrylic-based binder resin is a copolymer of a first
ethylenic unsaturated monomer and a second ethylenic unsaturated
monomer that is copolymerizable with the first ethylenic
unsaturated monomer, and a resin including at least one
acrylic-based repeating unit.
[0058] The first ethylenic unsaturated monomer is an ethylenic
unsaturated monomer including at least one carboxyl group. Examples
of the monomer include without limitation acrylic acid, methacrylic
acid, maleic acid, itaconic acid, fumaric acid, and the like, and
combinations thereof.
[0059] The copolymer may include the first ethylenic unsaturated
monomer in an amount ranging from about 5 to about 50 wt %, for
example, from about 10 to about 40 wt %, based on the total weight
of the acrylic-based binder resin. In some embodiments, the
copolymer may include the first ethylenic unsaturated monomer in an
amount of about 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50 wt %.
Further, according to some embodiments of the present invention,
the amount of the first ethylenic unsaturated monomer can be in a
range from about any of the foregoing amounts to about any other of
the foregoing amounts.
[0060] Examples of the second ethylenic unsaturated monomer may
include without limitation aromatic vinyl compounds such as
styrene, .alpha.-methylstyrene, vinyltoluene,
vinylbenzylmethylether, and the like; unsaturated carboxylic acid
ester compounds such as methyl(meth)acrylate, ethyl(meth)acrylate,
butyl(meth)acrylate, 2-hydroxyethyl(meth)acrylate, 2-hydroxy
butyl(meth)acrylate, benzyl(meth)acrylate,
cyclohexyl(meth)acrylate, phenyl(meth)acrylate, and the like;
unsaturated carboxylic acid amino alkyl ester compounds such as
2-aminoethyl(meth)acrylate, 2-dimethylaminoethyl(meth)acrylate, and
the like; a carboxylic acid vinyl ester compound such as vinyl
acetate, vinyl benzoate, and the like; unsaturated carboxylic acid
glycidyl ester compounds such as glycidyl(meth)acrylate and the
like; vinyl cyanide compounds such as (meth)acrylonitrile and the
like; unsaturated amide compounds such as (meth)acrylamide and the
like; and the like, and combinations thereof.
[0061] Examples of the acrylic-based binder resin may include
without limitation a methacrylic acid/benzylmethacrylate copolymer,
a methacrylic acid/benzylmethacrylate/styrene copolymer, a
methacrylic acid/benzylmethacrylate/2-hydroxyethylmethacrylate
copolymer, a methacrylic
acid/benzylmethacrylate/styrene/2-hydroxyethylmethacrylate
copolymer, and the like, and combinations thereof.
[0062] The acrylic-based binder resin may have a weight average
molecular weight ranging from about 3,000 to about 150,000 g/mol,
for example about 5,000 to about 50,000 g/mol, and as another
example about 2,000 to about 30,000 g/mol. When the acrylic-based
binder resin has a weight average molecular weight within the above
range, the photosensitive resin composition can have improved
physical and chemical properties and suitable viscosity, which can
improve close contacting (adhesion) properties with a substrate
during fabrication of a color filter.
[0063] The acrylic-based binder resin may have an acid value
ranging from about 15 to about 60 mgKOH/g, for example about 20 to
about 50 mgKOH/g. When the acrylic-based binder resin has an acid
value within the above range, excellent pixel resolution may be
realized.
[0064] The photosensitive resin composition may include the
acrylic-based binder resin in an amount of about 1 to about 30 wt
%, for example about 5 to about 20 wt %, based on the total weight
of the photosensitive resin composition for a color filter. In some
embodiments, the photosensitive resin composition may include the
acrylic-based binder resin in an amount of about 1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, or 30 wt %. Further, according to some
embodiments of the present invention, the amount of the
acrylic-based binder resin can be in a range from about any of the
foregoing amounts to about any other of the foregoing amounts.
[0065] When the acrylic-based binder resin is included in an amount
within the above range, improved developability may be provided
during manufacture of a color filter, and the cross-linking
property can be improved to obtain excellent smooth surface
properties.
[0066] (C) Photopolymerizable Monomer
[0067] The photopolymerizable monomer may be a mono-functional or
multi-functional ester of (meth)acrylic acid including at least one
ethylenic unsaturated double bond.
[0068] The photopolymerizable monomer can promote sufficient
polymerization when the composition is exposed during pattern
forming processes to form patterns having excellent heat
resistance, light resistance, and chemical resistance, due to the
ethylenic unsaturated double bond.
[0069] Examples of the photopolymerizable monomer include without
limitation ethylene glycol di(meth)acrylate, diethylene glycol
di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene
glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate,
1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate,
bisphenol A di(meth)acrylate, pentaerythritol di(meth)acrylate,
pentaerythritol tri(meth)acrylate, pentaerythritol
tetra(meth)acrylate, pentaerythritol hexa(meth)acrylate,
dipentaerythritol di(meth)acrylate, dipentaerythritol
tri(meth)acrylate, dipentaerythritol penta(meth)acrylate,
dipentaerythritol hexa(meth)acrylate, bisphenol A
epoxy(meth)acrylate, ethylene glycol monomethylether
(meth)acrylate, trimethylol propane tri(meth)acrylate,
tris(meth)acryloyloxyethyl phosphate, novolac epoxy (meth)acrylate,
and the like, and combinations thereof.
[0070] Commercially available examples of the photopolymerizable
monomer are as follows. The mono-functional (meth)acrylic acid
ester may include without limitation Aronix M-101.RTM., M-111.RTM.,
M-114.RTM. (TOAGOSEI CHEMICAL INDUSTRY CO., LTD.); KAYARAD
TC-110S.RTM., TC-120S.RTM. (NIPPON KAYAKU CO., LTD.); V-158.RTM.,
V-2311.RTM. (OSAKA ORGANIC CHEMICAL IND., LTD.), and the like.
Examples of a difunctional (meth)acrylic acid ester may include
without limitation Aronix M-210.RTM., M-240.RTM., M-6200.RTM.
(TOAGOSEI CHEMICAL INDUSTRY CO., LTD.), KAYARAD HDDA.RTM.,
HX-220.RTM., R-604.RTM. (NIPPON KAYAKU CO., LTD.), V-260.RTM.,
V-312.RTM., V-335 HP.RTM. (OSAKA ORGANIC CHEMICAL IND., LTD.), and
the like. Examples of a tri-functional (meth)acrylic acid ester may
include without limitation Aronix M-309.RTM., M-400.RTM.,
M-405.RTM., M-450.RTM., M-7100.RTM., M-8030.RTM., M-8060.RTM.
(TOAGOSEI CHEMICAL INDUSTRY CO., LTD.), KAYARAD TMPTA.RTM.,
DPCA-20.RTM., DPCA-30.RTM., DPCA-60.RTM., DPCA-120.RTM. (NIPPON
KAYAKU CO., LTD.), V-295.RTM., V-300.RTM., V-360.RTM., V-GPT.RTM.,
V-3PA.RTM., V-400.RTM. (Osaka Yuki Kayaku Kogyo Co. Ltd.), and the
like. The photopolymerizable monomer may be used singularly or as a
mixture of two or more.
[0071] The photopolymerizable monomer may be treated with acid
anhydride to improve developability.
[0072] The photosensitive resin composition may include the
photopolymerizable monomer in an amount ranging from about 1 to
about 15 wt %, for example about 5 to about 10 wt %, based on the
total weight of the photosensitive resin composition. In some
embodiments, the photosensitive resin composition may include the
photopolymerizable monomer in an amount of about 1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12, 13, 14, or 15 wt %. Further, according to some
embodiments of the present invention, the amount of the
photopolymerizable monomer can be in a range from about any of the
foregoing amounts to about any other of the foregoing amounts.
[0073] When the photopolymerizable monomer is included in an amount
within the above range, curing when exposed during pattern forming
processes can be sufficiently performed, and alkali development
property can be excellent.
[0074] (D) Photopolymerization Initiator
[0075] Examples of the photopolymerization initiator may include
without limitation acetophenone-based compounds, benzophenone-based
compounds, thioxanthone-based compounds, benzoin-based compounds,
triazine-based compounds, oxime-based compounds, and the like, and
combinations thereof.
[0076] Examples of the acetophenone-based compound may include
without limitation 2,2'-diethoxy acetophenone, 2,2'-dibutoxy
acetophenone, 2-hydroxy-2-methylpropinophenone, p-t-butyltrichloro
acetophenone, p-t-butyldichloro acetophenone, 4-chloro
acetophenone, 2,2'-dichloro-4-phenoxy acetophenone,
2-methyl-1-(4-(methylthio)phenyl)-2-morpholinopropan-1-one,
2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, and
the like, and combinations thereof.
[0077] Examples of the benzophenone-based compound may include
without limitation benzophenone, benzoyl benzoate, benzoyl methyl
benzoate, 4-phenyl benzophenone, hydroxy benzophenone, acrylated
benzophenone, 4,4'-bis(dimethyl amino)benzophenone,
4,4'-bis(diethylamino)benzophenone, 4,4'-dimethylaminobenzophenone,
4,4'-dichlorobenzophenone, 3,3'-dimethyl-2-methoxybenzophenone, and
the like, and combinations thereof.
[0078] Examples of the thioxanthone-based compound may include
without limitation thioxanthone, 2-methylthioxanthone, isopropyl
thioxanthone, 2,4-diethyl thioxanthone, 2,4-diisopropyl
thioxanthone, 2-chlorothioxanthone, and the like, and combinations
thereof.
[0079] Examples of the benzoin-based compound may include without
limitation benzoin, benzoin methyl ether, benzoin ethyl ether,
benzoin isopropyl ether, benzoin isobutyl ether,
benzyldimethylketal, and the like, and combinations thereof.
[0080] Examples of the triazine-based compound may include without
limitation 2,4,6-trichloro-s-triazine, 2-phenyl
4,6-bis(trichloromethyl)-s-triazine,
2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine,
2-(4'-methoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine,
2-(p-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine,
2-(p-tolyl)-4,6-bis(trichloro methyl)-s-triazine, 2-biphenyl
4,6-bis(trichloro methyl)-s-triazine,
bis(trichloromethyl)-6-styryl-s-triazine, and the like, and
combinations thereof.
[0081] Examples of the oxime-based compound may include without
limitation
2-(o-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octandione,
1-(o-acetyloxime)-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanon-
e, and the like, and combinations thereof.
[0082] The photopolymerization initiator may further include a
carbazole-based compound, a diketone-based compound, a sulfonium
borate-based compound, a diazo-based compound, an imidazole-based
compound, a biimidazole-based compound, and the like, or a
combination thereof.
[0083] The photosensitive resin composition may include the
photopolymerization initiator in an amount of about 0.1 to about 10
wt %, for example about 0.5 to about 5 wt %, based on the total
weight of the photosensitive resin composition. In some
embodiments, the photosensitive resin composition may include the
photopolymerization initiator in an amount of about 0.1, 0.2, 0.3,
0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10
we/o. Further, according to some embodiments of the present
invention, the amount of the photopolymerization initiator can be
in a range from about any of the foregoing amounts to about any
other of the foregoing amounts.
[0084] When the photopolymerization initiator is included in an
amount within the above range, the composition can be sufficiently
cured when exposed during pattern forming processes with minimal or
no deterioration of transmittance due to non-reacted
initiators.
[0085] (E) Solvent
[0086] The solvent is compatible with the dye, pigment,
acrylic-based binder resin, photopolymerizable monomer, and
photopolymerization initiator but does not react therewith.
[0087] Examples of the solvent may include without limitation
alcohols such as methanol, ethanol, and the like; ethers such as
dichloroethyl ether, n-butyl ether, diisoamyl ether, methylphenyl
ether, tetrahydrofuran, and the like; glycol ethers such as
ethylene glycol monomethylether, ethylene glycol monoethylether,
and the like; cellosolve acetates such as methyl cellosolve
acetate, ethyl cellosolve acetate, diethyl cellosolve acetate, and
the like; carbitols such as methylethyl carbitol, diethyl carbitol,
diethylene glycol monomethylether, diethylene glycol
monoethylether, diethylene glycol dimethylether, diethylene glycol
methylethylether, diethylene glycol diethylether, and the like;
propylene glycol alkylether acetates such as propylene glycol
methylether acetate, propylene glycol propylether acetate, and the
like; aromatic hydrocarbon such as toluene, xylene, and the like;
ketones such as methylethylketone, cyclohexanone,
4-hydroxy-4-methyl-2-pentanone, methyl-n-propylketone,
methyl-n-butylketone, methyl-n-amylketone, 2-heptanone, and the
like; saturated aliphatic monocarboxylic acid alkyl ester such as
ethyl acetate, n-butyl acetate, isobutyl acetate, and the like;
lactic acid alkyl esters such as methyl lactate, ethyl lactate, and
the like; hydroxyacetic acid alkyl esters such as methyl
hydroxyacetate, ethyl hydroxyacetate, butyl hydroxyacetate, and the
like; acetic acid alkoxyalkyl esters such as methoxymethyl acetate,
methoxyethyl acetate, methoxybutyl acetate, ethoxymethyl acetate,
ethoxyethyl acetate, and the like; 3-hydroxypropionic acid alkyl
esters such as methyl 3-hydroxypropionate, ethyl
3-hydroxypropionate, and the like; 3-alkoxypropionic acid alkyl
esters such as methyl 3-methoxypropionate, ethyl
3-methoxypropionate, ethyl 3-ethoxypropionate, methyl
3-ethoxypropionate, and the like; 2-hydroxypropionic acid alkyl
esters such as methyl 2-hydroxypropionate, ethyl
2-hydroxypropionate, propyl 2-hydroxypropionate, and the like;
2-alkoxypropionic acid alkyl esters such as methyl
2-methoxypropionate, ethyl 2-methoxypropionate, ethyl
2-ethoxypropionate, methyl 2-ethoxypropionate, and the like;
2-hydroxy-2-methylpropionic acid alkyl esters such as methyl
2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate,
and the like; 2-alkoxy-2-methylpropionic acid alkyl esters such as
methyl 2-methoxy-2-methylpropionate, ethyl
2-ethoxy-2-methylpropionate, and the like; esters such as
2-hydroxyethyl propionate, 2-hydroxy-2-methylethyl propionate,
hydroxyethyl acetate, methyl 2-hydroxy-3-methylbutanoate; ketonic
acid esters such as ethyl pyruvate; and the like, and combinations
thereof. Furthermore, the solvent may be N-methylformamide,
N,N-dimethyl formamide, N-methylformanilide, N-methylacetamide,
N,N-dimethyl acetamide, N-methylpyrrolidone, dimethylsulfoxide,
benzylethylether, dihexylether, acetyl acetone, isophorone, caproic
acid, caprylic acid, 1-octanol, 1-nonanol, benzyl alcohol, benzyl
acetate, ethyl benzoate, diethyl oxalate, diethyl maleate,
.gamma.-butyrolactone, ethylene carbonate, propylene carbonate,
phenyl cellosolve acetate, and the like. These solvents may be used
singularly or in combination.
[0088] Taking into consideration miscibility and reactivity, the
solvent can include glycol ethers such as ethylene glycol
monoethylether, and the like; ethylene glycol alkylether acetates
such as ethyl cellosolve acetate, and the like; esters such as
2-hydroxy ethyl propionate, and the like; diethylene glycols such
as diethylene glycol monomethylether, and the like; propylene
glycol alkylether acetates such as propylene glycol methylether
acetate, propylene glycol propylether acetate, and the like, and
combinations thereof.
[0089] The solvent may be used in a balance amount. In exemplary
embodiments, the photosensitive resin composition may include the
solvent in an amount of about 20 to about 90 wt % based on the
total weight of the photosensitive resin composition. In some
embodiments, the photosensitive resin composition may include the
solvent in an amount of about 20, 21, 22, 23, 24, 25, 26, 27, 28,
29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45,
46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62,
63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
80, 81, 82, 83, 84, 85, 86, 87, 88, 89, or 90 wt %. Further,
according to some embodiments of the present invention, the amount
of the solvent can be in a range from about any of the foregoing
amounts to about any other of the foregoing amounts.
[0090] When the solvent is included in an amount within the above
range, the photosensitive resin composition may have good coating
properties and can provide a film having a thickness of 3 .mu.m or
more with excellent flatness.
[0091] (F) Other Additive(s)
[0092] The photosensitive resin composition for a color filter may
further include one or more other additives such as but not limited
to malonic acid; 3-amino-1,2-propanediol; a silane-based coupling
agent including a vinyl group or a (meth)acryloxy group; a leveling
agent; a fluorine-based surfactant; a radical polymerization
initiator; and the like, and combinations thereof, to prevent
stains, improve leveling performance, and also prevent residues
from being generated due to undevelopment. The amount of these
additives may be readily determined by the skilled artisan without
undue experimentation, and the amounts may vary depending on the
desired composition properties.
[0093] Examples of the silane-based coupling agent may include
without limitation trimethoxysilyl benzoate, .gamma.-methacryl
oxypropyl trimethoxysilane, vinyl triacetoxysilane, vinyl
trimethoxysilane, .gamma.-isocyanate propyl triethoxysilane,
.gamma.-glycidoxy propyl trimethoxysilane,
.beta.-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and the like,
and combinations thereof.
[0094] Examples of the fluorine-based surfactant may include
without limitation BM-1000.RTM., and BM-1100.RTM. (BM Chemie Inc.);
MEGAFACE F 142D.RTM., F 172.RTM., F 173.RTM., and F 183.RTM.
DAINIPPON INK KAGAKU KOGYO CO., LTD.); FULORAD FC-135.RTM., FULORAD
FC-170C.RTM., FULORAD FC-430.RTM., and FULORAD FC-431.RTM.
(SUMITOMO 3M CO., LTD.); SURFLON S-112.RTM., SURFLON S-113.RTM.,
SURFLON S-131.RTM., SURFLON S-141.RTM., and SURFLON S-145.RTM.
(ASAHI GLASS CO., LTD.); and SH-28PA.RTM., SH-190.RTM.,
SH-193.RTM., SZ-6032.RTM., and SF-8428.RTM., and the like (TORAY
SILICONE CO., LTD.), and combinations thereof.
[0095] The photosensitive resin composition may further include an
epoxy compound in order to improve close contacting properties with
a substrate.
[0096] Examples of the epoxy compound include without limitation
phenol novolac epoxy compounds, tetramethyl biphenyl epoxy
compounds, bisphenol A epoxy compounds, alicyclic epoxy compounds,
and the like and combinations thereof.
[0097] The photosensitive resin composition may include the epoxy
compound in an amount of about 0.01 to about 5 parts by weight, for
example about 0.1 to about 5 parts by weight, based on about 100
parts by weight of the photosensitive resin composition. When the
epoxy compound is included in an amount within the above range,
close contacting properties, heat resistance, and chemical
resistance may be improved.
[0098] According to another embodiment, a color filter manufactured
using the photosensitive resin composition is provided. The color
filter can be manufactured as follows.
[0099] The photosensitive resin composition can be coated to a
thickness of about 3.1 to about 3.4 .mu.m on a bare glass substrate
or a glass substrate having an about 500 .ANG. to about 1500 .ANG.
thick SiN.sub.x layer (protective layer) thereon by a method such
as but not limited to spin coating, slit coating, and the like.
After the coating step, the coating can be exposed to radiation
(irradiated by light) to form a pattern required for a color
filter. When the coating layer is treated with an alkali
development solution to dissolve the non-radiated part, a pattern
for a color filter is formed. This process can be repeated as many
times as necessary, depending on the numbers of colors of R, G, B
and a light blocking layer needed to provide a color filter with a
desired pattern.
[0100] In this process, the developed image pattern can be heated
or cured by actinic rays to improve crack resistance, solvent
resistance, and the like.
[0101] The following examples illustrate the present invention in
more detail. However, it is understood that the present invention
is not limited by these examples.
[0102] (Preparation of Photosensitive Resin Composition for Color
Filter)
[0103] Components for preparing the photosensitive resin
composition for a color filter are as follows:
[0104] (A) Colorant
[0105] (A-1) A dye represented by the following Chemical Formula 2
(manufactured by KISCO, R91006) is used.
##STR00006##
[0106] (A-2) Pigment Dispersion
[0107] The following pigment dispersions (A-2a) and (A-2b) are
mixed at a weight ratio of 6:4 and used.
[0108] (A-2a) CHR50-R254 (manufactured by MIKUNI, pigment solid of
14.75 wt %)
[0109] (A-2b) CHR50-R177 (manufactured by MIKUNI, pigment solid of
12.88 wt %)
[0110] (C) Acrylic-Based Binder Resin
[0111] An acrylic acid/benzylmethacrylate copolymer (manufactured
by Miwon Commercial Co., Ltd., NPR1520) is used.
[0112] (D) Photopolymerizable Monomer
[0113] Dipentaerythritol hexaacrylate is used.
[0114] (E) Photopolymerization Initiator
[0115] CGI-124 manufactured by Ciba Specialty Chemical Co., Ltd. is
used.
[0116] (F) Solvent
[0117] Propylene glycol monomethyl ether acetate and ethyl
3-ethoxypropionate are used.
[0118] (G) Surfactant
[0119] A fluorine-based surfactant (F-475, manufactured by DIC) is
used.
Example 1
[0120] 1.7 g of the photopolymerization initiator is dissolved in a
solvent including 30.4 g of propylene glycol monomethyl ether
acetate and 17.0 g of 3-ethoxy ethyl propionate and agitated at a
room temperature for 2 hours. Then it is added with 9.0 g of dye
represented by Chemical Formula 2, 3.5 g of the acrylic-based
binder resin, and 8.5 g of the photopolymerizable monomer and
agitated at a room temperature for 2 hours. 29.7 g of the pigment
dispersion is added thereto and agitated at a room temperature for
one hour, and 0.2 g of the surfactant is added thereto and agitated
at a room temperature for one hour. The solution is filtered for
three times to remove impurities and to provide a photosensitive
resin composition for a color filter.
Example 2
[0121] A photosensitive resin composition for a color filter is
prepared in accordance with the same procedure as in Example 1,
except that 1.2 g of the dye and 37.5 g of the dye dispersion are
used.
Comparative Example 1
[0122] A photosensitive resin composition for a color filter is
prepared in accordance with the same procedure as in Example 1,
except that 38.7 g of the dye dispersion is used and no pigment is
used.
[0123] (Preparation of Filter for Color Filter)
[0124] Each photosensitive resin composition obtained from Examples
1 and 2 and Comparative Example 1 is coated on a degreased 1
mm-thick glass substrate to a thickness of 2 .mu.m and dried on a
hot plate of 90.degree. C. for 2 minutes to provide a coating
layer. Using a high pressure mercury lamp having a wavelength of
365 nm, the coating layer is exposed and dried in a dry oven at
160.degree. C. for 20 minutes to provide a pattern for a color
filter.
[0125] Assessment 1: Luminance and Contrast Ratio
[0126] The color coordinate and luminance and contrast ratio are
measured using the obtained pattern for a color filter in
accordance with the following methods, and the results are shown in
the following Table 1.
[0127] (1) Color coordinates (x and y) and luminance (Y)
measurements: measured using a spectrophotometer (manufactured by
Otsuka Electronic Co., MCPD 3000).
[0128] (2) Contrast ratio measurement: measured using a contrast
ratio measurer (manufactured by Tsubosaka electronic, CT-1,
30,000:1).
TABLE-US-00001 TABLE 1 Color coordinate Luminance X y Y Contrast
ratio Example 1 0.651 0.325 18.6 16,800 Example 2 0.651 0.325 18.4
16,050 Comparative 0.651 0.325 18.3 15,300 Example 1
[0129] As shown in Table 1, Examples 1 and 2 including colorants
according to one embodiment have higher luminance and contrast
ratio than Comparative Example 1.
[0130] Although not wishing to be bound by any explanation or
theory of the invention, it is currently believed that the high
luminance results from increasing the amount of high transmitting
pigment due to the high color representation of dye. The high
contrast ratio may be also explained as a result of decreasing
unnecessary light scattering since the dye has a solubility in an
organic solvent that is different from the solubility of the
pigment dispersion to provide no particles or particles with a
significantly smaller first diameter than the pigment in the
photosensitive resin composition for a color filter.
[0131] Assessment 2: Durability
[0132] The durability is measured by using the obtained pattern for
a color filter according to the following method, and the results
are shown in the following Table 2.
[0133] The durability is measured according to (1) a method of
dipping into a N-methylpyrrolidone (NMP) solvent at a room
temperature for 30 minutes, (2) a method of dipping a mixed solvent
(volume ratio=5:5) of N-methylpyrrolidone (NMP) and
ethylethoxypropinonate (EEP) at 80.degree. C. for 10 minutes, and
(3) a method of exposing to a Zenon lamp with 1MJ. .DELTA.Eab* is
obtained by using the color value difference between before and
after the treatment. If the obtained .DELTA.Eab* value is in 3, it
indicates a satisfying reliability. The less .DELTA.Eab* is, the
better durability is provided.
TABLE-US-00002 TABLE 2 .DELTA.Eab* (C) Light (A) NMP (B) NMP + EEP
resistance Example 1 1.19 0.98 2.27 Example 2 1.18 0.73 2.28
Comparative 1.21 1.03 2.31 Example 1
[0134] As shown in Table 2, Examples 1 and 2 including a colorant
according to one embodiment have better durability than Comparative
Example 1.
[0135] Many modifications and other embodiments of the invention
will come to mind to one skilled in the art to which this invention
pertains having the benefit of the teachings presented in the
foregoing descriptions. Therefore, it is to be understood that the
invention is not to be limited to the specific embodiments
disclosed and that modifications and other embodiments are intended
to be included within the scope of the appended claims. Although
specific terms are employed herein, they are used in a generic and
descriptive sense only and not for purposes of limitation, the
scope of the invention being defined in the claims.
* * * * *